A tradition still fairly prevalent in tropical Africa, for example, is that of farming by the extended family, under the direction of its head. This involved, and still involves, the great disadvantage that the main economic power is given to the older people, who tend to be less amenable to progress. This likelihood is increased by the fact that the average age of village head-men, who are also entrusted with considerable economic power by the community, is even higher than that of the heads of large families.